The present invention relates broadly to apparatus for cutting, tracing, or milling arcs in a workpiece and, more particularly, to an apparatus for tracing, milling, or cutting circular or elliptical arcs with variable radii and focal distances in wood or metal.
When making door or window frames, it sometimes becomes desirable to form an archway over the window or door frame. Typically, an arc that forms an archway is not formed as a perfect half-circle but rather includes curves or multiple radii in conjunction with one another.
Typically, these arches are cut or assembled from wood. Currently, techniques for forming the arches include using a preconfigured jig, manually tracing the arc on the wood for carving or through the use of computer controlled machinery with the attendant complexity and cost. Another technique is to employ a copying machine which traces a template and a remote unit that produces the arc on the wood as a duplicate of the template.
All of the above-discussed techniques have problems. The copy machines require the production of a template while separate jigs and manual tracing are difficult operations. Further, apart from computer control, it is difficult to produce different sized arcs without substantial manual adjustment of the device in use. Further, computer-controlled machines are expensive to use and produce. The common result of all these attempts is high manufacturing costs for the archways.